package controller;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


public class SessionFilter  implements Filter{

	@Override
	public void destroy() {
		
		
	}

	@Override
	public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
			throws IOException, ServletException {
		HttpServletRequest request = (HttpServletRequest)req;
		HttpServletResponse response = (HttpServletResponse)res;
		String requestPath = request.getRequestURI();
		//System.out.println("用户想请求:"+request.getRequestURI());
		if (requestPath.equals("/exam8_23/")||requestPath.equals("/exam8_23/login.jsp")||requestPath.equals("/exam8_23/UserinfoServlet")) {
			//放行
			chain.doFilter(req, res);
			return;
		}
		
		if (request.getSession().getAttribute("userid") == null) {
			response.sendRedirect("login.jsp");
		}else {
			chain.doFilter(request, response);
		}
		
				
	}
	
		

	@Override
	public void init(FilterConfig arg0) throws ServletException {
		
		
	}

	

}
